Near field Raman microscopy

With regard to the confinement and enhancement ability of a metallic nano-tip, we have proposed near-field Raman microscopy using a metallic nano-tip [9]. The metallic nano-tip is able to enhance not only the illuminating light but also the Raman scattered light [9, 15, 16]. Figure 2.5 illustrates our nano-Raman microscope that mainly comprises an inverted microscope for illumination and collection of Raman... 

Hartschuh, A., E.J. Sanchez, X.S. Xie, and L. Novotny. 2003. High-resolution near-field Raman microscopy of single-walled carbon nanotubes. Phys. Rev. Lett. 90 095503. 

Near Field Raman Microscopy (Micro-Spectroscopy)... 

In our tip-enhanced near-field CARS microscopy, two mode-locked pulsed lasers (pulse duration 5ps, spectral width 4cm ) were used for excitation of CARS polarization [21]. The sample was a DNA network nanostructure of poly(dA-dT)-poly(dA-dT) [24]. The frequency difference of the two excitation lasers (cOi — CO2) was set at 1337 cm, corresponding to the ring stretching mode of diazole. After the on-resonant imaging, CO2 was changed such that the frequency difference corresponded to none of the Raman-active vibration of the sample ( off-resonant ). The CARS images at the on- and off- resonant frequencies are illustrated in Figure 2.8a and b, respectively. 

SNOM) or Near-field scanning optical microscopy (NSOM) Scanning near-field raman spectroscopy (SNRS)... 

Ichimura T, Hayazawa N, Hashimoto M, Inouye Y, Kawata S (2004) Application of tip-enhanced microscopy for nonlinear Raman spectroscopy. Appl Phys Lett 84 1768 Ichimura T, Hayazawa N, Hashimoto M, Inouye Y, Kawata S (2004) Tip-enhanced coherent anti-stokes raman scattering for vibrational nanoimaging. Phys Rev Lett 92 220801 Tanaka S, Maeda Y, Cai L, Tabata H, Kawai T (2001) Application of tip-enhanced microscopy for nonlinear Raman spectroscopy. Jpn J Appl Phys 40 4217 Watanabe H, Ishida Y, Hayazawa N, Inouye Y, Kawata S (2004) Tip-enhanced near-field Raman analysis of tip-pressurized adenine molecule. Phys Rev B 69 155418 Yano T, Verma P, Saito Y, Ichimura T, Kawata S (2009) Pressure-assisted tip-enhanced Raman imaging at a resolution of a few nanometres. Nature Photon 3 473 Yano T, Inouye Y, Kawata S (2006) Nanoscale uniaxial pressure effect of a carbon nanotube bundle on tip-enhanced near-field Raman spectra. Nano Lett 6 1269 Downes A, Salter D, Elfick A (2006) Heating effects in tip-enhanced optical microscopy. Opt Exp 14 5216... 

If one includes the employment of evanescent light waves in spectroscopic studies in the near-field area. Knoll and coworkers are among the first who reported on near-field Raman spectroscopy , though this approach was termed at that time (the early 1990s) as surface plasmon field-enhanced Raman spectroscopy and microscopy [104],... 

Near-field optical microscopy in combination with Raman spectroscopy for the analysis of surfaces and interfaces and - because of the outstanding lateral resolution - for subcellular monitoring of molecular dynamics and single molecule detection. 

B. Introduction to Raman Scanning Near-Field Optical Microscopy... 

Scanning near-field optical microscopy is a technique that provides a way of circumventing the optical diffraction limit SNOM images with a spatial resolution of A/20 have been reported [27-33]. Because SNOM is an optical technique, it may be used to perform Raman spectroscopy with sub-A/2 spatial resolution [34-47]. 

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